Magazine insertions guides have found success in firearm competitions that involve quick changing of a magazine of the firearm (e.g., pistol) to enable this operation to be performed in a faster manner. Conventional magazine insertion guides, however, are bulky and thus limited to use in competition. Further, these conventional guides are limited to use by specific firearms, and even specific firearm/backstrap combinations for those firearms that support changeable backstraps to vary a grip diameter of a pistol grip, thus requiring multiple guides for even a single style of grip for each type of firearm.